You can achieve the same using AJAX.
Easy way would be to use UpdatePanel for the same: Keeping small things aside, in short, put your needed area in an Udpate Panel to enable partial rendering. Here you go:
UpdatePanel Control Overview[
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UpdatePanel control[
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UpdatePanel Class[
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All you need to know with sample code is present and explained.
Nutshell: You need to put your related area in an Udpate Panel and have menu actions as triggers to enable partial rendering.